One of several pieces of software from Microsoft:
1.
Windows 1.0 was a
graphical shell that allowed the user of an IBM PC to have several
MS-DOS programs running at the same time, sharing the screen through viewports called "windows," hence the name. It was released after the first Apple
Macintosh computer, and most users did not install it because it required too much memory. MS-DOS was an operating system that could only have one application open at any given time, and those applications could only access up to
640 kilobytes of RAM. Files stored by it had names consisting of eight characters,
a dot, and three more characters, and certain characters, such as spaces, were not allowed. TEXTFILE.TXT was a typical
DOS filename.
2. ~
3.0 was a graphical shell that also had dynamic library support, a feature normally built into an operating system. Applications had to be written "for" ~, almost as if it was an operating system. It did things on behalf of applications, like an operating system. It was started from DOS as an application, and exiting ~ returned the user to DOS. Instead of folders, there were program groups, where programs had to be explicitly placed. Placement of a program in the Program Groups typically involved telling ~ the complete path to the program
executable (ie, "C:\
COREL\
WP.EXE")
3. ~ 95 was a graphical shell that was booted directly by DOS, so that it appeared to be the entire operating system. It imitated the look and feel of a Macintosh. It was capable of running most ~
NT binaries, and it implemented pre-emptive
multitasking, a feature commonly found in
operating systems, and added support for "long filenames" (
LFN), which allowed files to have Macintosh-like names. The "Restart in DOS mode" feature is equivalent to the "Exit Windows" feature in older versions of ~.
4.
Windows NT ("New" Technology) is a real operating system that was written completely independantly of the line of graphical shells that are also called Windows. Microsoft hired the employees of DEC that designed
VMS to work on ~ NT. Unlike ~ versions that were already on the market, ~ NT took full advantage of the
Intel 386's 32-bit capabilities. Its design was so closely tied to the Intel 32-bit architecture that it could not be
ported to a 64-bit platform easily.
The "New" technology in ~ was new only to Windows. Features new to NT, such as true multitasking and virtual memory, had been available in other operating systems since the 1970s and even before that.
Microsoft eventually began to market Windows NT as an alternative to
UNIX, but they did so at the same time that Linux was becoming ever more popular as a UNIX replacement. Windows NT had many bugs of its own, and its superficial similarities to
Windows 95 caused users to expect Windows 95 bugs to be present in Windows NT. Its Internet server offerings were notably inferior to the UNIX programs they were meant to replace.
All current versions of Windows are descended from Windows NT, and not from the DOS shells that were also called Windows.
Though 64-bit Intel processors are already available in 2004, a 64-bit version of Windows is still years away.